 The route designations were changed to their present form when I-90 was moved to follow the entire length of the Kennedy Expressway and the Jane Addams Tollway, and the original route was designated I-290.The Chicago Skyway was originally known as the Calumet Skyway.It cost $101 million (1958, $791 million in 2011) to construct and took about 34 months (nearly 3 years) to build.